1. Field of the Invention
The present invention relates to the field of image recording devices, and more particularly to a digital 3D/360 degree camera system. The digital 3D/360° camera system utilizes a plurality of stereoscopic camera pairs to capture image data covering an entire 360° scene that may be used to create a 3D image, a 3D movie, or 3D animation.
2. Description of the Related Art
The advent of digital cameras of increasing resolution and photo quality, along with constantly increasing speed and processing power of computers, has laid the foundation for a 3-dimensional, 360° digital camera system capable of capturing image data for the creation of 3-dimensional images, movies, animation, and telepresence.
3-dimensional photography is not new. 3-dimensional photography has been available for over one hundred years through stereoscopic cameras. In a stereoscopic camera system, two cameras are used to capture a scene, each from a slightly different vantage point. The camera configuration is typically similar to the human eyes; with two cameras side-by-side and capturing two separate, but largely overlapping, views. The two images are viewed together through a stereoscopic viewer, giving the visual perception of three dimensions where the images overlap.
U.S. Pat. No. 1,957,043, issued to J. Harlow on May 1, 1934, describes a stereoscopic camera and viewing device. Such simple stereoscopic photography does nothing to achieve an expanded or panoramic field of view. Additionally, because the result of a stereoscopic photo is intended for direct human viewing through a stereoscopic viewer, the camera and the images it produces must conform to constraints of comfortable human viewing. For optimal human stereographic viewing, the field of view and the degree of overlap of the images must approximate the human eyes. Modern digital image processing can use computer technology to take advantage of images that fall well outside of these constraints, since images may be taken for the purpose of digital processing and not for direct human viewing.
Panoramic photography, the taking of a photograph or photographs covering a field of view that is wide to an entire 360° panorama, has a long history in photography. Perhaps the most primitive method of panoramic photography is the taking of several adjoining photos with a conventional camera and then mounting the prints together in alignment to achieve a complete panorama. Modern techniques adapt this method by using digital cameras to capture the image, and then using computer image processing techniques to align the images for printing as a single panoramic image.
U.S. Pat. No. 5,646,679, issued on Jul. 8, 1997 to K. Yano et al., discloses an image combining method and apparatus that uses a pair of digital cameras to capture separate overlapping images. The overlapping portions of the images are used to correlate the images for alignment. With the separate images aligned, a single image over a wide field of view may be created. An image processing system then combines the images for viewing.
U.S. Pat. No. 6,005,987, issued to M. Nakamura et al. on Dec. 21, 1999, shows a picture image forming apparatus that similarly forms a panoramic picture image by joining separate picture images. Like Yano, the Nakamura apparatus uses the overlapping regions of the images to align and join the images. The Nakamura apparatus additionally corrects deviations and distortions in the overlap regions.
While achieving improved panoramic photography, these methods do not provide the visual image data necessary to produce a 3-dimensional image or model. Additionally, where a panorama is composed of several individually exposed images, the result is limited in quality and utility by the dimension of time. Where the several images are exposed separately over a period of time, elements in the scene that may have moved are captured in different positions in the separate images. The result may be an image with unsynchronized moving elements within the exposures, rendering the images difficult or impossible to join, or a joined panoramic view with double images.
An alternative method of capturing a panoramic image is to capture the entire panorama in a single exposure. One such approach has been to use a camera with a rotating lens, or a rotating camera. In a film camera, a rotating lens can expose a strip of film as the lens sweeps the entire 360° view.
Another approach to a single-exposure panoramic camera is disclosed in U.S. Patent Publication No. 2001/0010555, published on Aug. 2, 2001. The panoramic camera uses a convex mirror to capture a 360° panorama in a 2-dimensional annular form. The annular image, digitally captured, is digitally transformed into a 2-dimensional rectangular image. While this approach solves the time-dimension problem by capturing the entire panoramic view in a single exposure, the result remains a 2-dimensional image that does not provide the image data needed to produce a 3-dimensional model or image.
U.S. Patent Publication No. 2001/0020976, published on Sep. 13, 2001, describes a stereo panoramic camera arrangement. This arrangement joins two panoramic cameras into a stereoscopic pair. In each of the cameras, a specialized mirror, or fresnel lens, is used to redirect the panoramic image for recording. One embodiment presented requires a cylindrical, rather than planar, optical element to record the image. Thus, while providing a panoramic camera with stereoscopic capability, this is not a solution that lends itself to the use of readily available and simple digital cameras.
U.S. Pat. No. 5,495,576, issued on Feb. 27, 1996 to K. Ritchie, discusses an audio-visual system that incorporates cameras to capture panoramic imagery, along with shape sensors to determine the 3-dimensional shape of a scene. The captured image is mapped to the shape to create a 3-dimensional model that may be processed for display on various 3-D display systems. The shape sensors are essentially radar, sonar, or similar sensors arrayed along with the cameras. The shape sensors function to gather information about the shape of objects in the field of view, primarily in terms of distance to the surface of the objects. Thus, the 3-dimensional model is the result of a combination of data sources rather than a product based strictly on stereoscopic image data.
U.S. Pat. No. 5,023,725, issued on Jun. 11, 1991 to D. McCutchen, discloses a dodecahedral imaging system in which several cameras are arranged in a dodecahedron. Along with the camera system, McCutchen discloses a projection dome with a dodecahedral shape to match the camera. While the system captures video of a generally spherical field of view for projection onto the interior surface of a dome or spherical theater, the video is not 3-dimensional. The cameras are not oriented to provide stereoscopic fields of view. The field of view of each camera is, in fact, cropped to align the various views for projection onto the interior of the dodecahedral dome with no overlap.
None of the above inventions and patents, taken either singly or in combination, is seen to describe the instant invention as claimed. Thus a digital 3D/360° camera system solving the aforementioned problems is desired.